1. Field of the Invention
The present invention relates to an apparatus for securing cabinet doors and specifically to a child safety lock to prevent children from gaining access to cabinets in kitchens and bathrooms.
2. Description of the Prior Art
The prior art discloses a wide variety of cabinet locks and child safety locks. For example, U.S. Pat. No. 5,360,243 discloses an electromagnetic lock with remote treadle for securing cabinets. U.S. Pat. No. 5,230,541 discloses a cabinet fastener with a flexible elongated band for securing paired handles of a cabinet. U.S. Pat. No. 4,984,833 discloses a lock hook for a door of a computer cabinet. U.S. Pat. No. 4,177,656 discloses a heavy duty cabinet lock. U.S. Pat. No. 3,475,929 discloses a portable locking device which requires a padlock. What is needed beyond the prior art is a child safety lock of simple and inexpensive design.
The present invention meets the needs and solves the problems identified above by providing an apparatus comprising modified cabinet doorknobs, a lock shaft and a pressure activated lock for mating with the connecting shaft. The modified cabinet doorknobs replace the existing doorknobs. In some cases, existing doorknobs may be altered to meet the requirements of the modified doorknobs. The modified doorknobs each have a knob shaft of a first diameter and a knob of a second diameter. The second diameter will always be larger than the first diameter. Each modified doorknob has a xc2xc inch hole running horizontally through the center shaft of the doorknob and parallel to the surface of the cabinet to which the doorknobs are to be attached. A typical doorknob has a knob of approximately 1 inch diameter and a shaft 3 xc2xc inches long and xe2x85x9c inch diameter. The modified doorknobs may be secured to the cabinet by a variety of means. In the preferred embodiment, the modified doorknobs are secured to the cabinet by 1xc2xc inch screws. A washer may be placed between the doorknob shaft and the cabinet door.
A lock shaft fits through the holes in the doorknobs. In the preferred embodiment, the lock shaft measures approximately 8 inches in length by {fraction (3/16)} inch in diameter and is made of plastic. The lock shaft has a first end to which a cross bar is affixed to prevent the lock shaft from passing completely through the holes. The lock shaft second end is rounded to facilitate passage through the holes. The cross bar is approximately 1 inch long. In the preferred embodiment, the lock shaft is approximately 8 inches long. In the preferred embodiment, the body of the lock shaft from the approximate center to the lock shaft second end has holes for receiving a spring loaded locking pin contained in the lock. Alternatively, the lock shaft may have grooves in the shaft for mating with a spring loaded window in the lock where the grooves are located from the approximate center to the second end may has holes for receiving a locking pin in the lock. Further in the alternative, the locking shaft may have circular flanges extending outward for mating with a spring loaded window in the lock where the flanges are located from the approximate center of the shaft to the second end.
The lock comprises a housing, a pin and a spring. Alternatively, the lock comprises a housing, an aperture and a spring. When a user presses down on the lock, the pin moves allowing passage of the lock shaft through the lock. When released, the pin engages the holes. Alternatively, the aperture engages the grooves or flanges of the lock shaft locking the shaft and preventing removal of the shaft from the lock. In the preferred embodiment, the housing measures approximately xc2xe inch by xc2xe inch.
To employ the lock, the user removes the existing doorknobs and replaces the doorknobs with modified doorknobs. To lock the cabinets, the user slides the second end of the lock shaft through the holes in the doorknobs until the lock shaft second end is completely through both doorknobs. The lock, with the spring depressed, is then slid over the second end of the lock shaft until the second end of the lock shaft is through the lock. The spring is then released so that the pin engages the holes, or alternatively, the aperture engages the grooves or flanges.
In an alternate embodiment, the lock shaft may be made approximately 12 to 14 inches long for use on single cabinets with drawers above the cabinet. The longer lock shaft would allow the lock to be used to pass through the single cabinet doorknob and the handle or knob of the drawer above the cabinet.
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention, as illustrated in the accompanying drawings wherein like reference numbers represent like parts of the invention.